Use Gem to install gems instead of invoking system

[rmNULL]

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Performing a gem install using system when a ruby program is running,
for unknown reasons( i couldn't figure out) fails to require the newly installed gem.
However by performing Gem.install the newly installed gem can be required.

Example for previously failing case

Homebrew.install_gem! "hola"
require 'hola' fails with LoadError

Other Notes / Doubts

Shell out to gem to avoid RubyGems requires for e.g. loading JSON.

deleted comment, i would like to know what this meant.

[MikeMcQuaid]

Thanks @rmNULL! I'm game for trying this but may need to revert if issues crop up.